一、硬件
上面红框是耳机插口，下面红框是Speaker插口。
首先，接上Speaker后，在Android 4.4上，耳机和Speaker都可以正常工作；但是，烧录R16开发板tina系统LCD调试编译的最新Tina系统，不工作。
二、调试
表面上，执行命令：
# cat cards /proc/asound/cards
0 [audiocodec ]: audiocodec - audiocodec
audiocodec
linux-3.4\sound\soc\sunxi\audiocodec\sunxi_sndcodec.c
static struct snd_soc_card snd_soc_sunxi_sndpcm = {
.name = "audiocodec",
.owner = THIS_MODULE,
.dai_link = &sunxi_sndpcm_dai_link,
.num_links = 1,
};
linux-3.4\sound\soc\sunxi\audiocodec\sun8iw5_machine.c
static struct snd_soc_card snd_soc_sunxi_sndpcm = {
.name = "sndcodec",
.owner = THIS_MODULE,
.dai_link = sunxi_sndpcm_dai_link,
.num_links = ARRAY_SIZE(sunxi_sndpcm_dai_link),
.dapm_widgets = sunxi_ac_dapm_widgets,
.num_dapm_widgets = ARRAY_SIZE(sunxi_ac_dapm_widgets),
.dapm_routes = audio_map,
.num_dapm_routes = ARRAY_SIZE(audio_map),
.controls = ac_pin_controls,
.num_controls = ARRAY_SIZE(ac_pin_controls),
.suspend_post = sunxi_suspend,
.resume_post = sunxi_resume,
};
但是，进一步发现这些差别只集中在\sound\soc目录下。这样我们可以直接替换soc代码，即把Android内核的soc目录copy覆盖Tina对应的目录，这时通过“aplay /www/ring.wav”可以正常播放，说明音频这部分OK了。
至于原因，等以后研究Linux的ALSA音频子系统后再细数。
三、tinyasla移植
Linux音频子系统框架：
图片来源：http://www.cnblogs.com/Ph-one/p/6293353.html
OSS音频架构已经depressed，所以系统是ALSA架构，“在ALSA音频架构下，App是通过ALSA提供的alsa-lib库访问底层硬件”，Android没有使用alsa-lib库，而是自己实现了一套API即tinyalsa，代码路径：external/tinyalsa。
我们看下tinyalsa的构成：
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES:= external/tinyalsa/include
LOCAL_SRC_FILES:= mixer.c pcm.c
LOCAL_MODULE := libtinyalsa
LOCAL_SHARED_LIBRARIES:= libcutils libutils
LOCAL_LDFLAGS += \
$(LOCAL_PATH)/libdrc.a
LOCAL_MODULE_TAGS := optional
LOCAL_PRELINK_MODULE := false
include $(BUILD_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES:= external/tinyalsa/include
LOCAL_SRC_FILES:= tinyplay.c
LOCAL_MODULE := tinyplay
LOCAL_SHARED_LIBRARIES:= libcutils libutils libtinyalsa
LOCAL_MODULE_TAGS := optional
include $(BUILD_EXECUTABLE)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES:= external/tinyalsa/include
LOCAL_SRC_FILES:= tinycap.c
LOCAL_MODULE := tinycap
LOCAL_SHARED_LIBRARIES:= libcutils libutils libtinyalsa
LOCAL_MODULE_TAGS := optional
include $(BUILD_EXECUTABLE)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES:= external/tinyalsa/include
LOCAL_SRC_FILES:= tinymix.c
LOCAL_MODULE := tinymix
LOCAL_SHARED_LIBRARIES:= libcutils libutils libtinyalsa
LOCAL_MODULE_TAGS := optional
include $(BUILD_EXECUTABLE)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES:= external/tinyalsa/include
LOCAL_SRC_FILES:= tinypcminfo.c
LOCAL_MODULE := tinypcminfo
LOCAL_SHARED_LIBRARIES:= libcutils libutils libtinyalsa
LOCAL_MODULE_TAGS := optional
include $(BUILD_EXECUTABLE)
2、tinyplay，播放
3、tinycap，录制
4、tinymix，控制声卡
5、tinypcminfo，查看声卡信息
为简单起见，移植过程中没有编译生成libtinyalsa库，而是作为源码编译，文件列表：
源码：https://github.com/RockyChing/tinyalsa.git
四、简单测试
# tinymix
tinymix
Mixer name: 'audiocodec'
Number of controls: 58
ctl type num name value
0 INT 1 headphone volume control 62
1 INT 1 earpiece volume control 62
2 INT 1 speaker volume control 62
3 INT 1 MIC1_G boost stage output mixer control 3
4 INT 1 MIC2_G boost stage output mixer control 3
5 INT 1 LINEIN_G boost stage output mixer control 3
6 INT 1 PHONE_G boost stage output mixer control 3
7 INT 1 PHONE_PG boost stage output mixer control 3
8 INT 1 PHONE_NG boost stage output mixer control 3
9 INT 1 MIC1 boost AMP gain control 4
10 INT 1 MIC2 boost AMP gain control 4
11 INT 1 Lineout volume control 62
12 INT 1 PHONEP-PHONEN pre-amp gain control 4
13 INT 1 Phoneout gain control 3
14 INT 1 ADC input gain ctrl 3
15 BOOL 1 Audio phone out Off
16 BOOL 1 Audio phone in Off
17 BOOL 1 Audio earpiece out Off
18 BOOL 1 Audio headphone out Off
19 BOOL 1 Audio speaker out Off
20 BOOL 1 Audio analog main mic Off
21 BOOL 1 Audio analog headsetmic Off
22 BOOL 1 Audio phone voicerecord Off
23 BOOL 1 Audio phone endcall Off
24 BOOL 1 Audio linein record Off
25 BOOL 1 Audio linein in Off
26 ENUM 1 Speaker Function spk
27 BOOL 1 Audio digital main mic Off
28 BOOL 1 Audio digital headset mic Off
29 BOOL 1 Audio digital phone out Off
30 BOOL 1 Audio digital phonein Off
31 BOOL 1 Audio digital clk format status Off
32 BOOL 1 Audio bt clk format status Off
33 BOOL 1 Audio bt out Off
34 BOOL 1 Audio analog bt mic Off
35 BOOL 1 Audio analog bt phonein Off
36 BOOL 1 Audio digital bt mic Off
37 BOOL 1 Audio digital bt phonein Off
38 BOOL 1 Audio bt button voice Off
39 BOOL 1 Audio digital bb bt clk format Off
40 BOOL 1 Audio system bt capture flag Off
41 BOOL 1 Audio analog bb capture mic Off
42 BOOL 1 aif3 loopback Off
43 BOOL 1 aif2 loopback Off
44 BOOL 1 digital_bb_bt Off
45 INT 1 system play_capture set 1 0
46 INT 1 system play_capture set 2 0
47 BOOL 1 AIF1_AD0L_MXR_SRC AIF1DA0Ldata Off
48 BOOL 1 AIF1_AD0L_MXR_SRC AIF2DACLdata Off
49 BOOL 1 AIF1_AD0L_MXR_SRC ADCLdata Off
50 BOOL 1 AIF1_AD0L_MXR_SRC AIF2DACRdata Off
51 BOOL 1 AIF1_AD0R_MXR_SRC AIF1DA0Rdata Off
52 BOOL 1 AIF1_AD0R_MXR_SRC AIF2DACRdata Off
53 BOOL 1 AIF1_AD0R_MXR_SRC ADCRdata Off
54 BOOL 1 AIF1_AD0R_MXR_SRC AIF2DACLdata Off
55 BOOL 1 Analog cap test disable phonein Off
56 BOOL 1 Analog cap test disable mic1 Off
57 BOOL 1 Analog cap test disable mic2 Offtinymix 2 2426 ENUM 1 Speaker Function spktinymix 26 headset
tinyplay xxx.wav